On Sat, Jul 16, 2016 at 02:23:48PM +0530, Bhaktipriya Shridhar wrote:
> The workqueue "work_thread" is involved in streaming the camera data.
> It has a single work item(&sd->work_struct) and hence doesn't require
> ordering. Also, it is not being used on a memory reclaim path.
> Hence, the singlethreaded workqueue has been replaced with the use of
> system_wq.
>
> System workqueues have been able to handle high level of concurrency
> for a long time now and hence it's not required to have a singlethreaded
> workqueue just to gain concurrency. Unlike a dedicated per-cpu workqueue
> created with create_singlethread_workqueue(), system_wq allows multiple
> work items to overlap executions even on the same CPU; however, a
> per-cpu workqueue doesn't have any CPU locality or global ordering
> guarantee unless the target CPU is explicitly specified and thus the
> increase of local concurrency shouldn't make any difference.
>
> Work item has been flushed in sd_stop0() to ensure that there are no
> pending tasks while disconnecting the driver.
>
> Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@xxxxxxxxx>